U.S. Pat. No. 006,043,997A disclosed a two stage, three-phase power boost factor correction circuit comprising a primary rectifier and a primary boost switch. The correction circuit is coupled between an input of three-phase power supply and an output of a three-phase boost converter. In the three-phase boost converter, a method of reducing input current total harmonic distortion (THD) at the input of the three-phase boost converter is to use an auxiliary stage including first, second and third pair auxiliary boost inductors coupled to corresponding inputs of the three phase power supply and the primary rectifier. The auxiliary stage also includes an auxiliary boost switch interposed between the first, second and third auxiliary boost inductors and the output so as to draw corresponding phase currents through the first, second and third auxiliary boost inductors, and thereby reducing input current THD at the input of the three-phase boost converter. The circuit has to process the whole power of the power supply, so that the efficiency is reduced and the cost is high.